Question

What is the easiest way to find the perimeter of a triangle

Answer 1

The easiest way is to write down the length of each side, and then add up
the three numbers.

In fact, that's the ONLY way to find the perimeter.  If anything else needs to
be done, that's usually because you don't know all three lengths yet, and
you have to find a missing length.  Once you accomplish that, you ALWAYS
find the perimeter by adding them up.

Answer 2

Add all the sides
side 1+ side 2+side 3= perimeter of the triangle